{{!

  Copyright (c) Meta Platforms, Inc. and affiliates.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

}}{{!

Generates a top-level file to be imported in the user's service code. It provides
wrappers for each of the service handlers that the user is then able to extend.

The generated file is pretty big, but the bulk of the generation is done inside
the services/promise and services/callback partials.

}}
{{^program:auto_migrate?}}
{{> common/auto_generated_py}}

cimport cython
from typing import AsyncIterator
from cpython.version cimport PY_VERSION_HEX
from libc.stdint cimport (
    int8_t as cint8_t,
    int16_t as cint16_t,
    int32_t as cint32_t,
    int64_t as cint64_t,
)
from libcpp.memory cimport shared_ptr, make_shared, unique_ptr
from libcpp.string cimport string
from libcpp cimport bool as cbool
from cpython cimport bool as pbool
from libcpp.vector cimport vector
from libcpp.set cimport set as cset
from libcpp.map cimport map as cmap
from libcpp.utility cimport move as cmove
from libcpp.pair cimport pair
from cython.operator cimport dereference as deref
from cpython.ref cimport PyObject
from thrift.python.exceptions cimport (
    ApplicationError as __ApplicationError,
    cTApplicationException,
    cTApplicationExceptionType__UNKNOWN,
)
from thrift.py3.server cimport ServiceInterface, RequestContext, Cpp2RequestContext
from thrift.py3.server import RequestContext
from folly cimport (
  cFollyPromise,
  cFollyUnit,
  c_unit,
)
from thrift.python.common cimport (
    cThriftServiceMetadataResponse as __fbthrift_cThriftServiceMetadataResponse,
    ServiceMetadata,
    MetadataBox as __MetadataBox,
)

from thrift.py3.server cimport THRIFT_REQUEST_CONTEXT as __THRIFT_REQUEST_CONTEXT
from thrift.py3.types cimport make_unique

cimport folly.futures
from folly.executor cimport get_executor
cimport folly.iobuf as _fbthrift_iobuf
import folly.iobuf as _fbthrift_iobuf
from folly.iobuf cimport move as move_iobuf
from folly.memory cimport to_shared_ptr as __to_shared_ptr

{{#program:has_stream?}}
from libcpp.optional cimport optional
from thrift.py3.stream cimport cServerStream, cServerStreamPublisher, cResponseAndServerStream, createResponseAndServerStream, createAsyncIteratorFromPyIterator, pythonFuncToCppFunc, ServerStream, ServerPublisher
{{/program:has_stream?}}
cimport {{#program:py3Namespaces}}{{value}}.{{/program:py3Namespaces}}{{program:name}}.types as _{{#program:py3Namespaces}}{{value}}_{{/program:py3Namespaces}}{{program:name}}_types
import {{#program:py3Namespaces}}{{value}}.{{/program:py3Namespaces}}{{program:name}}.types as _{{#program:py3Namespaces}}{{value}}_{{/program:py3Namespaces}}{{program:name}}_types
{{#program:includeNamespaces}}
{{#hasServices?}}
cimport {{#includeNamespace}}{{value}}.{{/includeNamespace}}services as _{{#includeNamespace}}{{value}}_{{/includeNamespace}}services
import {{#includeNamespace}}{{value}}.{{/includeNamespace}}services as _{{#includeNamespace}}{{value}}_{{/includeNamespace}}services
{{/hasServices?}}
{{#hasTypes?}}
import {{#includeNamespace}}{{value}}.{{/includeNamespace}}types as _{{#includeNamespace}}{{value}}_{{/includeNamespace}}types
cimport {{#includeNamespace}}{{value}}.{{/includeNamespace}}types as _{{#includeNamespace}}{{value}}_{{/includeNamespace}}types
{{/hasTypes?}}
{{/program:includeNamespaces}}

import {{#program:py3Namespaces}}{{value}}.{{/program:py3Namespaces}}{{program:name}}.services_reflection as _services_reflection
cimport {{#program:py3Namespaces}}{{value}}.{{/program:py3Namespaces}}{{program:name}}.services_reflection as _services_reflection

import asyncio
import functools
import sys
import traceback
import types as _py_types

{{#program:services}}
from {{#program:py3Namespaces}}{{value}}.{{/program:py3Namespaces}}{{program:name}}.services_wrapper cimport c{{service:name}}Interface
{{/program:services}}
{{#program:stream_types}}
cdef class ServerPublisher_{{> types/cython_cpp_type_ident}}(ServerPublisher):
    cdef unique_ptr[cServerStreamPublisher[{{!
            }}{{> types/cython_cpp_type}}{{!
        }}]] cPublisher

    def complete(ServerPublisher self):
        cmove(deref(self.cPublisher)).complete()

    # Calling this send instead of the wrapped method name of next because next is
    # a python keyword and makes the linter complain
    def send(ServerPublisher self, {{> types/cython_python_type}} item):
        deref(self.cPublisher).next(<{{> types/cython_cpp_type}}?>{{> types/cython_python_to_cpp_item}})

    @staticmethod
    cdef _fbthrift_create(cServerStreamPublisher[{{!
            }}{{> types/cython_cpp_type}}{{!
        }}] cPublisher):
        cdef ServerPublisher_{{> types/cython_cpp_type_ident}} inst = ServerPublisher_{{> types/cython_cpp_type_ident}}.__new__(ServerPublisher_{{> types/cython_cpp_type_ident}})
        inst.cPublisher = make_unique[cServerStreamPublisher[{{!
            }}{{> types/cython_cpp_type}}{{!
        }}]](cmove(cPublisher))
        return inst

cdef class ServerStream_{{> types/cython_cpp_type_ident}}(ServerStream):
    cdef unique_ptr[cServerStream[{{!
            }}{{> types/cython_cpp_type}}{{!
        }}]] cStream

    @staticmethod
    cdef _fbthrift_create(cServerStream[{{!
            }}{{> types/cython_cpp_type}}{{!
        }}] cStream):
        cdef ServerStream_{{> types/cython_cpp_type_ident}} inst = ServerStream_{{> types/cython_cpp_type_ident}}.__new__(ServerStream_{{> types/cython_cpp_type_ident}})
        inst.cStream = make_unique[cServerStream[{{!
            }}{{> types/cython_cpp_type}}{{!
        }}]](cmove(cStream))
        return inst
{{/program:stream_types}}

{{#program:services}}
{{#service:supportedFunctions}}
{{#function:return_type}}
{{#function:stream?}}
{{#function:stream_elem_type}}
async def runGenerator_{{service:name}}_{{function:name}}(object generator, Promise_{{> types/cython_cpp_type_ident}}_Stream promise):
    try:
        item = await generator.asend(None)
    except StopAsyncIteration:
        promise.cPromise.setValue(optional[{{> types/cython_cpp_type}}]())
    {{#function:stream_exceptions}}
    {{#field:type}}
    except {{> types/cython_python_type}} as ex:
        promise.cPromise.setException(deref((<{{> types/cython_python_type}}> ex).{{> types/cpp_obj}}))
    {{/field:type}}
    {{/function:stream_exceptions}}
    except __ApplicationError as ex:
        # If the handler raised an ApplicationError convert it to a C++ one
        promise.cPromise.setException(cTApplicationException(
            ex.type.value, ex.message.encode('UTF-8')
        ))
    except Exception as ex:
        print(
            "Unexpected error in {{service:name}}.{{function:name}}:",
            file=sys.stderr)
        traceback.print_exc()
        promise.cPromise.setException(cTApplicationException(
            cTApplicationExceptionType__UNKNOWN, repr(ex).encode('UTF-8')
        ))
    except asyncio.CancelledError as ex:
        print("Coroutine was cancelled in service handler {{service:name}}.{{function:name}}:", file=sys.stderr)
        traceback.print_exc()
        promise.cPromise.setException(cTApplicationException(
            cTApplicationExceptionType__UNKNOWN, (f'Application was cancelled on the server with message: {str(ex)}').encode('UTF-8')
        ))
    else:
        promise.cPromise.setValue(optional[{{> types/cython_cpp_type}}](<{{> types/cython_cpp_type}}?>{{> types/cython_python_to_cpp_item}}))

cdef void getNextGenerator_{{service:name}}_{{function:name}}(object generator, cFollyPromise[optional[{{> types/cython_cpp_type}}]] cPromise) noexcept:
    cdef Promise_{{> types/cython_cpp_type_ident}}_Stream __promise = Promise_{{> types/cython_cpp_type_ident}}_Stream._fbthrift_create(cmove(cPromise))
    asyncio.get_event_loop().create_task(
        runGenerator_{{service:name}}_{{function:name}}(
            generator,
            __promise
        )
    )
{{/function:stream_elem_type}}
{{/function:stream?}}
{{/function:return_type}}
{{/service:supportedFunctions}}
{{/program:services}}
{{> services/promise}}
{{> stream/stream_promises}}

{{#program:services}}
cdef object _{{service:name}}_annotations = _py_types.MappingProxyType({
{{#service:annotations}}
    {{> common/annotation}}
    {{#last?}}

    {{/last?}}
{{/service:annotations}}
})


@cython.auto_pickle(False)
cdef class {{service:name}}Interface(
    {{#service:extends}}{{#service:externalProgram?}}
    _{{#service:py3Namespaces}}{{value}}_{{/service:py3Namespaces}}{{!
        }}{{service:programName}}_services.{{/service:externalProgram?}}{{service:name}}Interface
    {{/service:extends}}
    {{^service:extends?}}
    ServiceInterface
    {{/service:extends?}}
):
    annotations = _{{service:name}}_annotations

    def __cinit__(self):
        self._cpp_obj = c{{service:name}}Interface(
            <PyObject *> self,
            get_executor()
        )
{{#service:supportedFunctions}}

    async def {{function:name}}(
            self{{#function:args}},
            {{field:py_name}}{{/function:args}}):
        raise NotImplementedError("async def {{function:name}} is not implemented")
    {{#function:return_type}}
    {{#function:stream?}}

    @staticmethod
    def createPublisher_{{function:name}}(callback=None):
        {{#function:stream_elem_type}}
        cdef unique_ptr[pair[cServerStream[{{> types/cython_cpp_type}}], {{!
        }}cServerStreamPublisher[{{> types/cython_cpp_type}}]]] streams = {{!
        }}make_unique[pair[cServerStream[{{> types/cython_cpp_type}}], {{!
        }}cServerStreamPublisher[{{> types/cython_cpp_type}}]]]({{!
        }}cServerStream[{{> types/cython_cpp_type}}].createPublisher(pythonFuncToCppFunc(callback)))

        return (ServerStream_{{> types/cython_cpp_type_ident}}._fbthrift_create(cmove(deref(streams).first)), {{!
        }}ServerPublisher_{{> types/cython_cpp_type_ident}}._fbthrift_create(cmove(deref(streams).second)))
        {{/function:stream_elem_type}}
    {{/function:stream?}}
    {{/function:return_type}}
{{/service:supportedFunctions}}

    @classmethod
    def __get_reflection__(cls):
        return _services_reflection.get_reflection__{{service:name}}(for_clients=False)

    @staticmethod
    def __get_metadata__():
        cdef __fbthrift_cThriftServiceMetadataResponse response
        ServiceMetadata[_services_reflection.c{{service:cpp_name}}SvIf].gen(response)
        return __MetadataBox.box(cmove(deref(response.metadata_ref())))

    @staticmethod
    def __get_thrift_name__():
        return "{{program:name}}.{{service:name}}"

{{/program:services}}

{{> services/callback}}
{{/program:auto_migrate?}}
